If you owe the IRS money and you aren't able to keep up or schedule a payment plan, they may start the process of garnishing your wages or other property through an IRS levy. The IRS can seize your legal property to offset the money you owe them for your taxes. If you know the IRS plans to levy your property, you only have a short amount of time to reverse the process.
A letter from Uncle Sam usually isn't good. And when it's in relation to levying an individual's property due to unpaid taxes, it's definitely an eye opener.